メタデータ
| 項目 |
値 |
| Designation |
C/2007 K3 (Siding Spring) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-04-21T17:04:30.377280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:08Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
13.300 |
| K1 |
13.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2008-02-09.0000000 |
| e |
1.00124061 |
| q (au) |
2.050740 |
| a (au) |
-1653.004343 |
| i (deg) |
16.300560 |
| Ω (om, deg) |
263.252666 |
| ω (w, deg) |
23.593153 |
| M (ma, deg) |
-0.001066 |
等級
散乱 + 全体線形
$$
M_a = (15.559 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.559 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.529 |
| k |
0.800 |
| δ90 |
10.000 |
| パラメータ |
記号 |
範囲 |
説明 |
| 太陽・地球距離が1 AUのときの絶対等級 |
H0 |
-5 to 20 |
彗星の固有の明るさ |
| 測光スロープパラメータ |
n |
2 to 6 |
太陽距離に対する明るさ変化率 |
| 前方散乱非対称係数 |
gf |
0.8 to 1 |
前方散乱の強さ |
| 後方散乱非対称係数 |
gb |
-1 to -0.5 |
後方散乱の強さ |
| 分配係数 |
k |
0.8 to 1 |
前方/後方散乱の寄与比 |
| ダスト/ガス明るさ比 |
δ90 |
1 to 10 |
ダスト散乱とガス放射の相対寄与 |
参考: EPSC-DPS2025-160
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2007-04-18 |
2007-07-18 |
-5.6530 |
+2.025 |
| 2008-06-09 |
2008-09-30 |
+25.5862 |
-9.589 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
05:19:52.10 |
+24:07:29.5 |
HIP 24875 |
18.05 |
| 2026-07-29 12:00 |
05:19:54.64 |
+24:07:31.8 |
HIP 24875 |
17.96 |
| 2026-07-30 00:00 |
05:19:57.16 |
+24:07:34.0 |
HIP 24994 |
17.47 |
| 2026-07-30 12:00 |
05:19:59.66 |
+24:07:36.3 |
HIP 24994 |
16.92 |
| 2026-07-31 00:00 |
05:20:02.14 |
+24:07:38.5 |
HIP 24994 |
16.37 |
| 2026-07-31 12:00 |
05:20:04.60 |
+24:07:40.7 |
HIP 24994 |
15.83 |
| 2026-08-01 00:00 |
05:20:07.04 |
+24:07:42.9 |
HIP 24994 |
15.30 |
| 2026-08-01 12:00 |
05:20:09.46 |
+24:07:45.1 |
HIP 24994 |
14.77 |
| 2026-08-02 00:00 |
05:20:11.86 |
+24:07:47.2 |
HIP 24994 |
14.26 |
| 2026-08-02 12:00 |
05:20:14.24 |
+24:07:49.4 |
HIP 24994 |
13.74 |
| 2026-08-03 00:00 |
05:20:16.60 |
+24:07:51.5 |
HIP 24994 |
13.24 |
| 2026-08-03 12:00 |
05:20:18.94 |
+24:07:53.6 |
HIP 24994 |
12.74 |
| 2026-08-04 00:00 |
05:20:21.25 |
+24:07:55.7 |
HIP 24994 |
12.25 |
| 2026-08-04 12:00 |
05:20:23.55 |
+24:07:57.8 |
HIP 24994 |
11.76 |
| 2026-08-05 00:00 |
05:20:25.82 |
+24:07:59.8 |
HIP 24994 |
11.29 |
| 2026-08-05 12:00 |
05:20:28.07 |
+24:08:01.9 |
HIP 24994 |
10.82 |
| 2026-08-06 00:00 |
05:20:30.30 |
+24:08:03.9 |
HIP 24994 |
10.36 |
| 2026-08-06 12:00 |
05:20:32.51 |
+24:08:05.9 |
HIP 24994 |
9.91 |
| 2026-08-07 00:00 |
05:20:34.69 |
+24:08:07.8 |
HIP 24994 |
9.48 |
| 2026-08-07 12:00 |
05:20:36.86 |
+24:08:09.8 |
HIP 24994 |
9.05 |
| 2026-08-08 00:00 |
05:20:39.00 |
+24:08:11.7 |
HIP 24994 |
8.63 |
| 2026-08-08 12:00 |
05:20:41.11 |
+24:08:13.7 |
HIP 24994 |
8.23 |
| 2026-08-09 00:00 |
05:20:43.21 |
+24:08:15.6 |
HIP 24994 |
7.84 |
| 2026-08-09 12:00 |
05:20:45.28 |
+24:08:17.4 |
HIP 24994 |
7.46 |
| 2026-08-10 00:00 |
05:20:47.33 |
+24:08:19.3 |
HIP 24994 |
7.10 |
| 2026-08-10 12:00 |
05:20:49.35 |
+24:08:21.2 |
HIP 24994 |
6.76 |
| 2026-08-11 00:00 |
05:20:51.36 |
+24:08:23.0 |
HIP 24994 |
6.43 |
| 2026-08-11 12:00 |
05:20:53.33 |
+24:08:24.8 |
HIP 24994 |
6.13 |
| 2026-08-12 00:00 |
05:20:55.29 |
+24:08:26.6 |
HIP 24994 |
5.84 |
| 2026-08-12 12:00 |
05:20:57.22 |
+24:08:28.3 |
HIP 24994 |
5.59 |
| 2026-08-13 00:00 |
05:20:59.12 |
+24:08:30.1 |
HIP 24994 |
5.36 |
| 2026-08-13 12:00 |
05:21:01.00 |
+24:08:31.8 |
HIP 24994 |
5.15 |
| 2026-08-14 00:00 |
05:21:02.86 |
+24:08:33.5 |
HIP 24994 |
4.98 |
| 2026-08-14 12:00 |
05:21:04.69 |
+24:08:35.2 |
HIP 24994 |
4.85 |
| 2026-08-15 00:00 |
05:21:06.50 |
+24:08:36.8 |
HIP 24994 |
4.74 |
| 2026-08-15 12:00 |
05:21:08.28 |
+24:08:38.5 |
HIP 24994 |
4.67 |
| 2026-08-16 00:00 |
05:21:10.04 |
+24:08:40.1 |
HIP 24994 |
4.64 |
| 2026-08-16 12:00 |
05:21:11.78 |
+24:08:41.7 |
HIP 24994 |
4.64 |
| 2026-08-17 00:00 |
05:21:13.48 |
+24:08:43.3 |
HIP 24994 |
4.67 |
| 2026-08-17 12:00 |
05:21:15.17 |
+24:08:44.8 |
HIP 24994 |
4.74 |
| 2026-08-18 00:00 |
05:21:16.82 |
+24:08:46.4 |
HIP 24994 |
4.83 |
| 2026-08-18 12:00 |
05:21:18.45 |
+24:08:47.9 |
HIP 24994 |
4.95 |
| 2026-08-19 00:00 |
05:21:20.06 |
+24:08:49.4 |
HIP 24994 |
5.09 |